The present invention relates to steel, more particularly to steel compositions and articles that are characterized by high-strength and high-toughness and that are suitable for ballistic or cryogenic use.
Steel is an alloy that contains iron and carbon. Steel is often used as a structural material, and has been known in a variety of formulations; generally speaking, steel properties will vary in accordance with steel formulations. Steel typically contains predominately iron, about 0.2% to 1.5% carbon (weight percent), and at least one other constituent such as aluminum, chromium, cobalt, copper, manganese, molybdenum, nickel, phosphorus, silicon, sulfur, or tungsten. Desirable properties of steel may include strength, toughness, durability, malleability, hardness, ductility, ballistic resistance, cryogenic efficacy, etc.
The following references, each of which is incorporated herein by reference, are informative on ballistic and other properties of steel: T. BØrvik, S. Dey and A. H. Clausen: Int. J. Impact Eng., 2009, 36, 948-964; J. F. Chinella and M. G. H. Wells: ARL-RP-64, US, February 2003; S. N. Dikshit, V. V. Kutumbarao and G. Sundararjan: Int. J. Impact Eng., 1995, 16, 293-320; W. Gooch, M. Burkins and D. Mackenzie: 22nd Int. Symposium on Ballistics, Vancouver, Canada, 2005; S. J. Manganello and K. H. Abbott: J. of Materials, 1972, 231-239; D. D. Showalter, W. A. Gooch, M. S. Burkins, J. S. Montgomery and R. Squillacioti: AMMTIAC, 2010, Vol. 4, No. 4, 2010; D. D. Showalter, W. A. Gooch, M. S. Burkins and R. Stockman Koch: ARL-TR-4632, US, 2008; D. D. Showalter, W. A. Gooch, M. S. Burkins, V. Thorn, S. Cimpoeru and R. Barnett: ARL-RP-181, US, 2007; D. D. Showalter, W. A. Gooch, M. Burskins, J. Montgomery and R. Squillacioti: ARL-TR-4997, 2009.